A person who demonstrates high standards, such as in doing a homework assignment meticulously, could be described as

meticulous, thorough, diligent, precise, conscientious

A person who demonstrates high standards, such as in doing a homework assignment meticulously, could be described as diligent.

A person who demonstrates high standards, such as doing a homework assignment meticulously, could be described as conscientious.

To arrive at this word, you can consider the following steps:

1. Identify the traits associated with someone who completes a task with great attention to detail and high standards.
2. Think of words that reflect these traits. For example, diligent, meticulous, thorough, or precise.
3. Among these options, the word "conscientious" stands out as a suitable choice for describing someone who consistently exhibits high standards in their work, paying careful attention to every detail.

By following this process, you can select apt adjectives to describe someone with specific attributes.